The dragon boundary marks are cast iron statues of dragons on metal or stone plinths that mark the boundaries of the City of London. The dragons are painted silver, with details of their wings and tongue picked out in red. The dragon stands on one rear leg, the other lifted against a shield, with the right foreleg raised and the left foreleg holding a shield which bears the City of London's coat of arms, painted in red and white. This stance is the equivalent of the rampant heraldic 'attitude' of the supporters of the City's arms.

The design is based on two large dragon sculptures, 7 feet (210 cm) high, which were mounted above the entrance to the Coal Exchangeon Lower Thames Street, designed by the City Architect, J. B. Bunning, and made by London founder, Dewer, in 1849. The dragons were preserved when the Coal Exchange was demolished in 1962–3. The two original statues were re-erected on 6 feet (180 cm) high plinths ofPortland stone at the western boundary of the City, by Temple Gardens on Victoria Embankment, in October 1963.